Layers
by Tammany Tiger
Summary: This is a shortie. It's conjecture passing itself off as story-but should be at least interesting for those who like conjecture and spec embedded in character dialogue. The actual characters are John and Sherlock; the topic of discussion is Lestrade, and to a lesser degree, Mycroft. The piece has the faintest lingering whiff of Moriarty. Time is soon after Hounds of Baskerville.


**Conjecture and speculation passing as story. I have tended to go with a head-canon for Lestrade and Mycroft that parallels that of others, connecting Lestrade to Sherlock, and to Mycroft through Sherlock. But the other day I chased an entirely different logic line down a rabbit-hole and came up with a conjecture that plays the association in the other direction, and makes the Lestrade/Mycroft connection potentially older than it would be otherwise. Have fun.**

Layers

"So, what—your brother met Lestrade through you, yeah?"

Sherlock, shoveling Chinese food from a carton with split-pine chopsticks, shook his head. "Other way around." He popped another piece of General Tso's into his mouth. Only when he had swallowed did he give a crooked grin and add, "I believe I'm a _legacy_, of sorts... though neither my brother nor Lestrade will admit it."

"A legacy?" John frowned, chasing a baby corn cob around his own carton of mu gu gai pan. "Mycroft''s not dead, yet." He waited for the inevitable Holy Grail quote—but Sherlock wasn't as culturally dependable as most of his generation.

"It sounds better than a going-away-present," Sherlock said, conceding the point. "I believe they were partners for some years, with Mycroft training under Greg when he first began in the secret service. But Mycroft became involved in higher and higher levels of analytical and bureaucratic work, and I have concluded that Greg was the perfect choice for an embed position in the Met—and getting a bit old for straight field work.'"

John sat up, scowling. "Wait. What? A moment, please. Greg's..."

Sherlock's brows raised, and he gave the sort of supercilious smirk he and his brother had honed to perfection. "Greg's what?"

Like he didn't know, John thought, a bit sourly. Sharp enough to cut himself, that was Sherlock. "Lestrade's MI5?"

Sherlock rolled his eyes, discarded his empty carton with a careless flip of the wrist, and rummaged around for the bag of eggrolls. "You really don't pay attention, do you? There's a reason I accused him of being my handler. For all practical purposes, he is. I am... well. Depending on when you ask Mycroft, I'm either a British asset or one of the 'usual suspects.' Either way, the security agencies like to keep an eye on me. _Et voilá_! Mycroft pulled Lestrade out of his hat: already embedded in the Met, and doing work in my field. I'm sure Mycroft considered it a near-miraculous convenience, and passed me on like a hot potato to his old mentor."

"Greg. _Our _Greg? Good old Lestrade? A cheerful snark for everyone? Patient as the day is long?"

"Um-hmmmm. Good, isn't he?"

John shook his head, trying to chase the sense of being invaded by a swarm of buzzing bees seeking a hive. His thoughts zipped around chaotically. "No. I don't believe it. Sherlock, I know you see patterns in everything, but... Greg? MI5? No."

"Yes."

"No."

"Are you going to make me prove it, John?"

John looked at his flatmate reprovingly. "I think you'd better."

"Very well. Let us take our recent adventure at Baskerville as a starting point for a proof, then. If my brother didn't alert Lestrade, how did he happen to be at our inn when we were there?"

"Coincidence?" John said, already convinced that hound wouldn't hunt.

Sherlock gave him a reproving glance, then dipped his eggroll in the hot mustard. "Not even remotely plausible. And it fails to pass Occam's razor. Given that a mutual associate with multiple existing concerns was aware of our presence at Baskerville, which is the simpler and more likely explanation: that Lestrade arrived by accident, or that he was sent?"

John had expected to give that round away. "All right. I'll accept your argument. Mycroft sent him."

"A policeman freshly returned from vacation—a vacation that marked the end of his marriage? How would Mycroft have the clout to free Inspector Lestrade from work that was no doubt piling up while he was gone—or override any lingering emotional apathy or irritability left by the divorce?"

"What? What divorce? What are you talking about?"

"Oh, come now. Even you're not that thick, John—Mrs. Hudson could solve this one, and would. Marital problems of an ongoing nature, extending back before last Christmas and the event with the PE teacher? Wedding ring gone, but only at the end of the recent vacation or the tan mark where he'd worn it would not have been so marked anyone could spot it?"

"_I_ didn't spot it," John grumbled.

"Mrs. Hudson would have," Sherlock said pointedly. "In any case, the emotional element isn't primary. The ability to remove an officer from his usual duties, though, is more problematic."

"Mycroft is the British Government, according to you," John said, snagging an eggroll for himself. "He could probably arrange for Her Majesty to take a day off to babysit you—corgis and all."

"No, no. Granted, I attended a few birthday parties, but they more or less banned me after I tried the experiment on Wills. It was just electricity, after all. It could have been worse. But you're missing the point: even Mycroft doesn't ignore proper channels. There are reasons Lestrade has gotten away with bending regulation to allow me to work with him, and more reasons he can bend his time card to rush off to Baskerville after already being gone long enough to develop a proper tan. People up the line—far up the line—know when to turn a blind eye, because it suits them to have a good working relationship with their embed and his bosses. Lestrade is damned careful never to push it. Mycroft is...usually careful. But not always. He'll go a step or two farther than Lestrade would, if he thinks it's worth risking Lestrade's cover."

John was about to say, "Oh, I'm sure Greg just loves that," when he realized that the comment would be as good as accepting Sherlock's premise. He wasn't willing to go that far, though. Instead he said, "And Greg could just as easily have been happy to escape one more day of paperwork and crime sites."

"Our Lestrade? England would fall if he were dragged from his duty!"

"But you're arguing it's not his duty: that he's really MI5 passing as a Met DI."

"Passing because he's good—and cares enough about the work to do it convincingly."

"I still don't believe it."

Sherlock grinned his entirely-too-satisfied grin. "Of course, John."

"Let me guess. You've got another three hours of proof if that didn't convince me?"

"I do, actually, but I only need to examine one more key element of the case to convince you, I think. There were two people carrying weapons at Dewer's Hollow. Henry, and Lestrade. One of those weapons was illegal, of course."

John nodded. "Henry's. Permits to carry as a civilian are rare to non-existent, and a man of questionable stability would never have been granted one." And, he thought, let's not talk about my service revolver... "I always thought it was good of Lestrade not to bring charges on that."

"Quite good—though in its own right that tolerance is a hint that Lestrade's servant to more than just police regulations. But Henry's gun is not the critical weapon—the key is the gun that was not illegal."

John frowned. "Yeah? What? Greg's gun, yeah?"

"You really don't see it, do you? Why did DI Lestrade have a gun, John?"

John frowned, thinking back as he dragged the fortune cookies from the bottom of the delivery container. "You asked him to bring it. When you called him."

"Yes, I did. And why would I ask DI Lestrade to bring a gun, John?"

"Because we needed armed backup."

"John, do think. You're not a complete fool. We are not America. It's not common for our police to carry firearms, and less for our police to carry them when off duty. Those who might are few and far between, and almost always serving in true front-line positions, rather than pottering around in investigations after the crimes are committed and the criminals have sensibly run away. Lestrade is an investigator, John. Under normal circumstances he would not be carrying a Glock. And on a military base, where no ordinary civilian should be armed? And would Lestrade bring along a weapon while on 'vacation?' You know Lestrade. You tell me. What would cause DI Lestrade—_'Our' _DI Lestrade— to carry an illegal weapon onto a military base with every intention of using it should it be necessary? Can you think of any time DI Lestrad would break the law that profoundly?"

John frowned, trying to work it through, then shook his head, feeling entirely muddled.

"Think about it, John. It's not that hard. Lestrade would only have been in that position willingly if the gun were legal, and Lestrade were entitled to use it on a military base in the performance of his duty."

"But you've proven it couldn't be legal and that it wasn't... Oh."

"Exactly," Sherlock said, with a smile. "If he were an MI5 embed charged with the protection and supervision of a wild-card talent, Lestrade might well have not only the right, but the duty to carry a firearm and use it in my defense."

"Oh, come on, Sherlock," John grumbled. "Are you telling me when you asked Lestrade to bring a gun you were thinking all that?"

"I'm telling you when I asked Lestrade to bring a gun, I had every reason to believe he could and would comply."

"Because..."

"Because I know Mycroft. And I know how few people he would entrust with my care."

John cracked open his fortune cookie, barely paying attention. He picked the fragments up, munching and pondering. "Lestrade... MI5?"

"MI5 seems most likely."

"And you're sure he worked with Mycroft?"

"There's a reason he finds it irritating to be considered my brother's errand boy now, when Lestrade helped train him. And a reason Mycroft trusts Lestrade to train me."

"You're sure? Really sure?"

"I...deduced it."

"So you're not sure."

"I'm as sure as I am that your fortune says 'Save the whales. Collect the whole set.'"

John scowled and glanced down at his fortune. "How did you... you know, that's a really stupid fortune. But how did you know?"

"You're not the only one who reads upside down."

"So you _can't_ deduce fortune cookie fortunes."

"_Almost_. I can certainly deduce them when the signs are so clear to read. That's how it is, John. Evidence is little different from print. The data is there, the detective reads it, the deductions are obvious."

John frowned, staring at his fortune. "How many layers down does it go, Sherlock?"

"Does what go?"

"Everything. You. Mycroft. Lestrade. Even me. How many layers are in play?"

"That depends on how you count. Looked at one way, much of my past year has been altered by layers that started piling up at the murder of a young boy in a swimming pool over twenty years ago. You tell me, John—how many layers does it take to create a legacy?"

John shook his head. "Not my area. I think you'll have to ask Mycroft that."

Sherlock looked calmly out the window of the apartment into the night streets outside. "And what if I already have, and even he's not sure?"

John shook his head.

And outside, the layers turned—and Jim Moriarty prepared to go a-wilding.


End file.
